1. Field
Embodiments of the invention relate to electronic devices, and more particularly, to amplifiers.
2. Description of the Related Technology
An amplifier, such as an operational amplifier, can include chopper circuitry to help reduce the amplifier's input offset voltage. For example, in a conventional chopper-stabilized amplifier, chopper circuitry can be used to periodically swap or chop the positive and negative inputs of an input amplification stage of the amplifier and to periodically swap or chop the positive and negative outputs of the amplifier's input amplification stage at a chopping frequency. Additionally, the amplifier can use an output amplification stage to generate the amplifier's output signal by integrating the input amplification stage's chopped output signal. Although including conventional chopper circuitry in an amplifier can reduce the amplifier's input offset voltage, configuring the amplifier in this manner can also generate ripples in the amplifier's output signal at the chopping frequency and at harmonics thereof.
There is a need for amplifiers having improved performance. Additionally, there is need for chopper stabilized amplifiers having reduced input offset voltage and reduced output voltage ripple.